In a vehicle, such as an electric vehicle and a hybrid vehicle, which is a type that travels using a motor, a structure is adopted in which a power supply apparatus serving as a drive source of the motor is mounted in a luggage compartment having a sufficient crushable zone secured against an external force acting from the rear side (a rear-end collision). With such a protection structure, the impact is absorbed by the crushable zone so that the load applied to the power supply apparatus is reduced. Also, a vehicle component is prevented from directly entering the power supply apparatus and damaging the power supply apparatus.
However, in such a protection structure, in the case in which a power supply apparatus is mounted in a narrow luggage compartment space of a smaller hatchback type vehicle and the like, there is a case in which a sufficient crushable zone cannot be secured against an external force due to a rear-end collision.
As a conventional technique of the power supply apparatus protection structure, there has been proposed a technique in which a power supply apparatus (secondary battery) is housed in a protection frame structure (frame unit) formed by a plurality of frames so as to enable an external force acting on the power supply apparatus to be suppressed (Patent Literature 1).